std::flat_multiset<Key,Compare,KeyContainer>::count

 

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std::flat_multiset

Member types

Member functions

flat_multiset::flat_multiset   flat_multiset::operator= Iterators flat_multiset::beginflat_multiset::cbegin flat_multiset::endflat_multiset::cend flat_multiset::rbeginflat_multiset::crbegin flat_multiset::rendflat_multiset::crend Capacity flat_multiset::size flat_multiset::max_size flat_multiset::empty Observers flat_multiset::key_comp flat_multiset::value_comp Modifiers flat_multiset::clear flat_multiset::insert flat_multiset::insert_range flat_multiset::emplace flat_multiset::emplace_hint flat_multiset::erase flat_multiset::swap flat_multiset::extract flat_multiset::replace Lookup flat_multiset::count flat_multiset::find flat_multiset::contains flat_multiset::equal_range flat_multiset::lower_bound flat_multiset::upper_bound

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swap(std::flat_multiset) erase_if(std::flat_multiset)    operator==operator<=>

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uses_allocator<std::flat_multiset>

Tags

sorted_equivalent         sorted_equivalent_t

Deduction guides

 

size_type count( const Key& key ) const;	(1)	(since C++23)
template< class K > size_type count( const K& x ) const;	(2)	(since C++23)

Returns the number of elements with key that compares equivalent to the specified argument.

1) Returns the number of elements with key key.

2) Returns the number of elements with key that compares equivalent to the value x. This overload participates in overload resolution only if the qualified-id Compare::is_transparent is valid and denotes a type. It allows calling this function without constructing an instance of Key.

Parameters

key	-	key value of the elements to count
x	-	alternative value to compare to the keys

Return value

Number of elements with key that compares equivalent to key or x.

Complexity

Logarithmic in the size of the container plus linear in the number of elements found.

See also

find	finds element with specific key (public member function)
equal_range	returns range of elements matching a specific key (public member function)